Opposition finance spokesman Andrew Robb said the giant telco would have preferred to not play ball but was intimidated by threats of structural separation.
"This is a deal struck out of intimidation and a gun at the head of Telstra," Mr Robb told reporters in Canberra.
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"If they didn't cooperate and hand over their facilities ... they would have had structural separation and their whole business plan would have collapsed."
The Telstra board had no alternative but to strike some deal, Mr Robb said.
In a major breakthrough in protracted negotiations on Sunday, it was announced Telstra will be paid $9 billion to effectively lease its existing infrastructure to NBN Co - the company that will build and operate the national broadband network.
The telco will also be paid $2 billion in compensation to cover costs associated with regulatory reform of the sector.
The terms of the lease were not disclosed but sources close to the negotiations told AAP the agreement was for a period much longer than 10 years.
Mr Robb says the agreement is a Clayton's deal.
"This is going to be the biggest infrastructure white elephant in our history.
"It is an obsession of this government to involve themselves in business activities."
